]> git.sur5r.net Git - freertos/blobdiff - FreeRTOS-Plus/Source/FreeRTOS-Plus-TCP/portable/NetworkInterface/WinPCap/NetworkInterface.c
Update version number in readiness for V10.3.0 release. Sync SVN with reviewed releas...
[freertos] / FreeRTOS-Plus / Source / FreeRTOS-Plus-TCP / portable / NetworkInterface / WinPCap / NetworkInterface.c
index 474629e4632d4a552efa3e2afe016bd053b53068..c4a12515b0891a151d7a5063428e77157ac80cf5 100644 (file)
-/*\r
-FreeRTOS+TCP V2.0.11\r
-Copyright (C) 2017 Amazon.com, Inc. or its affiliates.  All Rights Reserved.\r
-\r
-Permission is hereby granted, free of charge, to any person obtaining a copy of\r
-this software and associated documentation files (the "Software"), to deal in\r
-the Software without restriction, including without limitation the rights to\r
-use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of\r
-the Software, and to permit persons to whom the Software is furnished to do so,\r
-subject to the following conditions:\r
-\r
-The above copyright notice and this permission notice shall be included in all\r
-copies or substantial portions of the Software.\r
-\r
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\r
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS\r
-FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR\r
-COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER\r
-IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN\r
-CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.\r
-\r
- http://aws.amazon.com/freertos\r
- http://www.FreeRTOS.org\r
-*/\r
-\r
-/* WinPCap includes. */\r
-#define HAVE_REMOTE\r
-#include "pcap.h"\r
-\r
-/* FreeRTOS includes. */\r
-#include "FreeRTOS.h"\r
-#include "task.h"\r
-#include "semphr.h"\r
-\r
-/* FreeRTOS+TCP includes. */\r
-#include "FreeRTOS_IP.h"\r
-#include "FreeRTOS_IP_Private.h"\r
-#include "NetworkBufferManagement.h"\r
-\r
-/* Thread-safe circular buffers are being used to pass data to and from the PCAP\r
-access functions. */\r
-#include "Win32-Extensions.h"\r
-#include "FreeRTOS_Stream_Buffer.h"\r
-\r
-/* Sizes of the thread safe circular buffers used to pass data to and from the\r
-WinPCAP Windows threads. */\r
-#define xSEND_BUFFER_SIZE  32768\r
-#define xRECV_BUFFER_SIZE  32768\r
-\r
-/* If ipconfigETHERNET_DRIVER_FILTERS_FRAME_TYPES is set to 1, then the Ethernet\r
-driver will filter incoming packets and only pass the stack those packets it\r
-considers need processing. */\r
-#if( ipconfigETHERNET_DRIVER_FILTERS_FRAME_TYPES == 0 )\r
-       #define ipCONSIDER_FRAME_FOR_PROCESSING( pucEthernetBuffer ) eProcessBuffer\r
-#else\r
-       #define ipCONSIDER_FRAME_FOR_PROCESSING( pucEthernetBuffer ) eConsiderFrameForProcessing( ( pucEthernetBuffer ) )\r
-#endif\r
-\r
-/* Used to insert test code only. */\r
-#define niDISRUPT_PACKETS      0\r
-\r
-/*-----------------------------------------------------------*/\r
-\r
-/*\r
- * Windows threads that are outside of the control of the FreeRTOS simulator are\r
- * used to interface with the WinPCAP libraries.\r
- */\r
-DWORD WINAPI prvWinPcapRecvThread( void *pvParam );\r
-DWORD WINAPI prvWinPcapSendThread( void *pvParam );\r
-\r
-/*\r
- * Print out a numbered list of network interfaces that are available on the\r
- * host computer.\r
- */\r
-static pcap_if_t * prvPrintAvailableNetworkInterfaces( void );\r
-\r
-/*\r
- * Open the network interface.  The number of the interface to be opened is set\r
- * by the configNETWORK_INTERFACE_TO_USE constant in FreeRTOSConfig.h.\r
- */\r
-static void prvOpenSelectedNetworkInterface( pcap_if_t *pxAllNetworkInterfaces );\r
-static int prvOpenInterface( const char *pucName );\r
-\r
-/*\r
- * Configure the capture filter to allow blocking reads, and to filter out\r
- * packets that are not of interest to this demo.\r
- */\r
-static void prvConfigureCaptureBehaviour( void );\r
-\r
-/*\r
- * A function that simulates Ethernet interrupts by periodically polling the\r
- * WinPCap interface for new data.\r
- */\r
-static void prvInterruptSimulatorTask( void *pvParameters );\r
-\r
-/*\r
- * Create the buffers that are used to pass data between the FreeRTOS simulator\r
- * and the Win32 threads that manage WinPCAP.\r
- */\r
-static void prvCreateThreadSafeBuffers( void );\r
-\r
-/*\r
- * Utility function used to format print messages only.\r
- */\r
-static const char *prvRemoveSpaces( char *pcBuffer, int aBuflen, const char *pcMessage );\r
-\r
-/*-----------------------------------------------------------*/\r
-\r
-/* Required by the WinPCap library. */\r
-static char cErrorBuffer[ PCAP_ERRBUF_SIZE ];\r
-\r
-/* An event used to wake up the Win32 thread that sends data through the WinPCAP\r
-library. */\r
-static void *pvSendEvent = NULL;\r
-\r
-/* _HT_ made the PCAP interface number configurable through the program's\r
-parameters in order to test in different machines. */\r
-static BaseType_t xConfigNetworkInterfaceToUse = configNETWORK_INTERFACE_TO_USE;\r
-\r
-/* Handles to the Windows threads that handle the PCAP IO. */\r
-static HANDLE vWinPcapRecvThreadHandle = NULL;\r
-static HANDLE vWinPcapSendThreadHandle = NULL;;\r
-\r
-/* The interface being used by WinPCap. */\r
-static pcap_t *pxOpenedInterfaceHandle = NULL;\r
-\r
-/* Circular buffers used by the PCAP Win32 threads. */\r
-static StreamBuffer_t *xSendBuffer = NULL;\r
-static StreamBuffer_t *xRecvBuffer = NULL;\r
-\r
-/* The MAC address initially set to the constants defined in FreeRTOSConfig.h. */\r
-extern uint8_t ucMACAddress[ 6 ];\r
-\r
-/* Logs the number of WinPCAP send failures, for viewing in the debugger only. */\r
-static volatile uint32_t ulWinPCAPSendFailures = 0;\r
-\r
-/*-----------------------------------------------------------*/\r
-\r
-BaseType_t xNetworkInterfaceInitialise( void )\r
-{\r
-BaseType_t xReturn = pdFALSE;\r
-pcap_if_t *pxAllNetworkInterfaces;\r
-\r
-       /* Query the computer the simulation is being executed on to find the\r
-       network interfaces it has installed. */\r
-       pxAllNetworkInterfaces = prvPrintAvailableNetworkInterfaces();\r
-\r
-       /* Open the network interface.  The number of the interface to be opened is\r
-       set by the configNETWORK_INTERFACE_TO_USE constant in FreeRTOSConfig.h.\r
-       Calling this function will set the pxOpenedInterfaceHandle variable.  If,\r
-       after calling this function, pxOpenedInterfaceHandle is equal to NULL, then\r
-       the interface could not be opened. */\r
-       if( pxAllNetworkInterfaces != NULL )\r
-       {\r
-               prvOpenSelectedNetworkInterface( pxAllNetworkInterfaces );\r
-       }\r
-\r
-       if( pxOpenedInterfaceHandle != NULL )\r
-       {\r
-               xReturn = pdPASS;\r
-       }\r
-\r
-       return xReturn;\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-static void prvCreateThreadSafeBuffers( void )\r
-{\r
-       /* The buffer used to pass data to be transmitted from a FreeRTOS task to\r
-       the Win32 thread that sends via the WinPCAP library. */\r
-       if( xSendBuffer == NULL)\r
-       {\r
-               xSendBuffer = ( StreamBuffer_t * ) malloc( sizeof( *xSendBuffer ) - sizeof( xSendBuffer->ucArray ) + xSEND_BUFFER_SIZE + 1 );\r
-               configASSERT( xSendBuffer );\r
-               memset( xSendBuffer, '\0', sizeof( *xSendBuffer ) - sizeof( xSendBuffer->ucArray ) );\r
-               xSendBuffer->LENGTH = xSEND_BUFFER_SIZE + 1;\r
-       }\r
-\r
-       /* The buffer used to pass received data from the Win32 thread that receives\r
-       via the WinPCAP library to the FreeRTOS task. */\r
-       if( xRecvBuffer == NULL)\r
-       {\r
-               xRecvBuffer = ( StreamBuffer_t * ) malloc( sizeof( *xRecvBuffer ) - sizeof( xRecvBuffer->ucArray ) + xRECV_BUFFER_SIZE + 1 );\r
-               configASSERT( xRecvBuffer );\r
-               memset( xRecvBuffer, '\0', sizeof( *xRecvBuffer ) - sizeof( xRecvBuffer->ucArray ) );\r
-               xRecvBuffer->LENGTH = xRECV_BUFFER_SIZE + 1;\r
-       }\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-BaseType_t xNetworkInterfaceOutput( NetworkBufferDescriptor_t * const pxNetworkBuffer, BaseType_t bReleaseAfterSend )\r
-{\r
-size_t xSpace;\r
-\r
-       iptraceNETWORK_INTERFACE_TRANSMIT();\r
-       configASSERT( xIsCallingFromIPTask() == pdTRUE );\r
-\r
-       /* Both the length of the data being sent and the actual data being sent\r
-       are placed in the thread safe buffer used to pass data between the FreeRTOS\r
-       tasks and the Win32 thread that sends data via the WinPCAP library.  Drop\r
-       the packet if there is insufficient space in the buffer to hold both. */\r
-       xSpace = uxStreamBufferGetSpace( xSendBuffer );\r
-\r
-       if( ( pxNetworkBuffer->xDataLength <= ( ipconfigNETWORK_MTU + ipSIZE_OF_ETH_HEADER ) ) &&\r
-               ( xSpace >= ( pxNetworkBuffer->xDataLength + sizeof( pxNetworkBuffer->xDataLength ) ) ) )\r
-       {\r
-               /* First write in the length of the data, then write in the data\r
-               itself. */\r
-               uxStreamBufferAdd( xSendBuffer, 0, ( const uint8_t * ) &( pxNetworkBuffer->xDataLength ), sizeof( pxNetworkBuffer->xDataLength ) );\r
-               uxStreamBufferAdd( xSendBuffer, 0, ( const uint8_t * ) pxNetworkBuffer->pucEthernetBuffer, pxNetworkBuffer->xDataLength );\r
-       }\r
-       else\r
-       {\r
-               FreeRTOS_debug_printf( ( "xNetworkInterfaceOutput: send buffers full to store %lu\n", pxNetworkBuffer->xDataLength ) );\r
-       }\r
-\r
-       /* Kick the Tx task in either case in case it doesn't know the buffer is\r
-       full. */\r
-       SetEvent( pvSendEvent );\r
-\r
-       /* The buffer has been sent so can be released. */\r
-       if( bReleaseAfterSend != pdFALSE )\r
-       {\r
-               vReleaseNetworkBufferAndDescriptor( pxNetworkBuffer );\r
-       }\r
-\r
-       return pdPASS;\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-static pcap_if_t * prvPrintAvailableNetworkInterfaces( void )\r
-{\r
-pcap_if_t * pxAllNetworkInterfaces = NULL, *xInterface;\r
-int32_t lInterfaceNumber = 1;\r
-char cBuffer[ 512 ];\r
-static BaseType_t xInvalidInterfaceDetected = pdFALSE;\r
-\r
-       if( xInvalidInterfaceDetected == pdFALSE )\r
-       {\r
-               if( pcap_findalldevs_ex( PCAP_SRC_IF_STRING, NULL, &pxAllNetworkInterfaces, cErrorBuffer ) == -1 )\r
-               {\r
-                       printf( "Could not obtain a list of network interfaces\n%s\n", cErrorBuffer );\r
-                       pxAllNetworkInterfaces = NULL;\r
-               }\r
-               else\r
-               {\r
-                       printf( "\r\n\r\nThe following network interfaces are available:\r\n\r\n" );\r
-               }\r
-\r
-               if( pxAllNetworkInterfaces != NULL )\r
-               {\r
-                       /* Print out the list of network interfaces.  The first in the list\r
-                       is interface '1', not interface '0'. */\r
-                       for( xInterface = pxAllNetworkInterfaces; xInterface != NULL; xInterface = xInterface->next )\r
-                       {\r
-                               /* The descriptions of the devices can be full of spaces, clean them\r
-                               a little.  printf() can only be used here because the network is not\r
-                               up yet - so no other network tasks will be running. */\r
-                               printf( "Interface %d - %s\n", lInterfaceNumber, prvRemoveSpaces( cBuffer, sizeof( cBuffer ), xInterface->name ) );\r
-                               printf( "              (%s)\n", prvRemoveSpaces(cBuffer, sizeof( cBuffer ), xInterface->description ? xInterface->description : "No description" ) );\r
-                               printf( "\n" );\r
-                               lInterfaceNumber++;\r
-                       }\r
-               }\r
-\r
-               if( lInterfaceNumber == 1 )\r
-               {\r
-                       /* The interface number was never incremented, so the above for() loop\r
-                       did not execute meaning no interfaces were found. */\r
-                       printf( " \nNo network interfaces were found.\n" );\r
-                       pxAllNetworkInterfaces = NULL;\r
-               }\r
-\r
-               printf( "\r\nThe interface that will be opened is set by " );\r
-               printf( "\"configNETWORK_INTERFACE_TO_USE\", which\r\nshould be defined in FreeRTOSConfig.h\r\n" );\r
-\r
-               if( ( xConfigNetworkInterfaceToUse < 1L ) || ( xConfigNetworkInterfaceToUse >= lInterfaceNumber ) )\r
-               {\r
-                       printf( "\r\nERROR:  configNETWORK_INTERFACE_TO_USE is set to %d, which is an invalid value.\r\n", xConfigNetworkInterfaceToUse );\r
-                       printf( "Please set configNETWORK_INTERFACE_TO_USE to one of the interface numbers listed above,\r\n" );\r
-                       printf( "then re-compile and re-start the application.  Only Ethernet (as opposed to WiFi)\r\n" );\r
-                       printf( "interfaces are supported.\r\n\r\nHALTING\r\n\r\n\r\n" );\r
-                       xInvalidInterfaceDetected = pdTRUE;\r
-\r
-                       if( pxAllNetworkInterfaces != NULL )\r
-                       {\r
-                               /* Free the device list, as no devices are going to be opened. */\r
-                               pcap_freealldevs( pxAllNetworkInterfaces );\r
-                               pxAllNetworkInterfaces = NULL;\r
-                       }\r
-               }\r
-               else\r
-               {\r
-                       printf( "Attempting to open interface number %d.\n", xConfigNetworkInterfaceToUse );\r
-               }\r
-       }\r
-\r
-       return pxAllNetworkInterfaces;\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-static int prvOpenInterface( const char *pucName )\r
-{\r
-static char pucInterfaceName[ 256 ];\r
-\r
-       if( pucName != NULL )\r
-       {\r
-               strncpy( pucInterfaceName, pucName, sizeof( pucInterfaceName ) );\r
-       }\r
-\r
-       pxOpenedInterfaceHandle = pcap_open(    pucInterfaceName,               /* The name of the selected interface. */\r
-                                                                                       ipTOTAL_ETHERNET_FRAME_SIZE, /* The size of the packet to capture. */\r
-                                                                                       PCAP_OPENFLAG_PROMISCUOUS,      /* Open in promiscuous mode as the MAC and\r
-                                                                                                                                               IP address is going to be "simulated", and\r
-                                                                                                                                               not be the real MAC and IP address.  This allows\r
-                                                                                                                                               traffic to the simulated IP address to be routed\r
-                                                                                                                                               to uIP, and traffic to the real IP address to be\r
-                                                                                                                                               routed to the Windows TCP/IP stack. */\r
-                                                                                       100,\r
-                                                                                       NULL,                                   /* No authentication is required as this is\r
-                                                                                                                                               not a remote capture session. */\r
-                                                                                       cErrorBuffer\r
-                                                                          );\r
-\r
-       if ( pxOpenedInterfaceHandle == NULL )\r
-       {\r
-               printf( "\n%s is not supported by WinPcap and cannot be opened\n", pucInterfaceName );\r
-               return 1;\r
-       }\r
-       else\r
-       {\r
-               /* Configure the capture filter to allow blocking reads, and to filter\r
-               out packets that are not of interest to this demo. */\r
-               prvConfigureCaptureBehaviour();\r
-       }\r
-       return 0;\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-static void prvOpenSelectedNetworkInterface( pcap_if_t *pxAllNetworkInterfaces )\r
-{\r
-pcap_if_t *pxInterface;\r
-int32_t x;\r
-\r
-       /* Walk the list of devices until the selected device is located. */\r
-       pxInterface = pxAllNetworkInterfaces;\r
-       for( x = 0L; x < ( xConfigNetworkInterfaceToUse - 1L ); x++ )\r
-       {\r
-               pxInterface = pxInterface->next;\r
-       }\r
-\r
-       /* Open the selected interface. */\r
-       if( prvOpenInterface( pxInterface->name ) == 0 )\r
-       {\r
-               printf( "Successfully opened interface number %d.\n", x + 1 );\r
-       }\r
-       else\r
-       {\r
-               printf( "Failed to open interface number %d.\n", x + 1 );\r
-       }\r
-\r
-       /* The device list is no longer required. */\r
-       pcap_freealldevs( pxAllNetworkInterfaces );\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-static void prvConfigureCaptureBehaviour( void )\r
-{\r
-struct bpf_program xFilterCode;\r
-uint32_t ulNetMask;\r
-\r
-       /* Set up a filter so only the packets of interest are passed to the IP\r
-       stack.  cErrorBuffer is used for convenience to create the string.  Don't\r
-       confuse this with an error message. */\r
-       sprintf( cErrorBuffer, "broadcast or multicast or ether host %x:%x:%x:%x:%x:%x",\r
-               ucMACAddress[0], ucMACAddress[1], ucMACAddress[2], ucMACAddress[3], ucMACAddress[4], ucMACAddress[5] );\r
-\r
-       ulNetMask = ( configNET_MASK3 << 24UL ) | ( configNET_MASK2 << 16UL ) | ( configNET_MASK1 << 8L ) | configNET_MASK0;\r
-\r
-       if( pcap_compile( pxOpenedInterfaceHandle, &xFilterCode, cErrorBuffer, 1, ulNetMask ) < 0 )\r
-       {\r
-               printf( "\nThe packet filter string is invalid\n" );\r
-       }\r
-       else\r
-       {\r
-               if( pcap_setfilter( pxOpenedInterfaceHandle, &xFilterCode ) < 0 )\r
-               {\r
-                       printf( "\nAn error occurred setting the packet filter.\n" );\r
-               }\r
-               /* When pcap_compile() succeeds, it allocates memory for the memory pointed to by the bpf_program struct \r
-               parameter.pcap_freecode() will free that memory. */\r
-               pcap_freecode( &xFilterCode );\r
-       }\r
-\r
-       /* Create the buffers used to pass packets between the FreeRTOS simulator\r
-       and the Win32 threads that are handling WinPCAP. */\r
-       prvCreateThreadSafeBuffers();\r
-\r
-       if( pvSendEvent == NULL )\r
-       {\r
-               /* Create event used to signal the Win32 WinPCAP Tx thread. */\r
-               pvSendEvent = CreateEvent( NULL, FALSE, TRUE, NULL );\r
-\r
-               /* Create the Win32 thread that handles WinPCAP Rx. */\r
-               vWinPcapRecvThreadHandle = CreateThread(\r
-                       NULL,   /* Pointer to thread security attributes. */\r
-                       0,              /* Initial thread stack size, in bytes. */\r
-                       prvWinPcapRecvThread,   /* Pointer to thread function. */\r
-                       NULL,   /* Argument for new thread. */\r
-                       0,              /* Creation flags. */\r
-                       NULL );\r
-\r
-               /* Use the cores that are not used by the FreeRTOS tasks. */\r
-               SetThreadAffinityMask( vWinPcapRecvThreadHandle, ~0x01u );\r
-\r
-               /* Create the Win32 thread that handlers WinPCAP Tx. */\r
-               vWinPcapSendThreadHandle = CreateThread(\r
-                       NULL,   /* Pointer to thread security attributes. */\r
-                       0,              /* initial thread stack size, in bytes. */\r
-                       prvWinPcapSendThread,   /* Pointer to thread function. */\r
-                       NULL,   /* Argument for new thread. */\r
-                       0,              /* Creation flags. */\r
-                       NULL );\r
-\r
-               /* Use the cores that are not used by the FreeRTOS tasks. */\r
-               SetThreadAffinityMask( vWinPcapSendThreadHandle, ~0x01u );\r
-\r
-               /* Create a task that simulates an interrupt in a real system.  This will\r
-               block waiting for packets, then send a message to the IP task when data\r
-               is available. */\r
-               xTaskCreate( prvInterruptSimulatorTask, "MAC_ISR", configMINIMAL_STACK_SIZE, NULL, configMAC_ISR_SIMULATOR_PRIORITY, NULL );\r
-       }\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-/* WinPCAP function. */\r
-void pcap_callback( u_char *user, const struct pcap_pkthdr *pkt_header, const u_char *pkt_data )\r
-{\r
-       (void)user;\r
-\r
-       /* THIS IS CALLED FROM A WINDOWS THREAD - DO NOT ATTEMPT ANY FREERTOS CALLS\r
-       OR TO PRINT OUT MESSAGES HERE. */\r
-\r
-       /* Pass data to the FreeRTOS simulator on a thread safe circular buffer. */\r
-       if( ( pkt_header->caplen <= ( ipconfigNETWORK_MTU + ipSIZE_OF_ETH_HEADER ) ) &&\r
-               ( uxStreamBufferGetSpace( xRecvBuffer ) >= ( ( ( size_t ) pkt_header->caplen ) + sizeof( *pkt_header ) ) ) )\r
-       {\r
-               uxStreamBufferAdd( xRecvBuffer, 0, ( const uint8_t* ) pkt_header, sizeof( *pkt_header ) );\r
-               uxStreamBufferAdd( xRecvBuffer, 0, ( const uint8_t* ) pkt_data, ( size_t ) pkt_header->caplen );\r
-       }\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-DWORD WINAPI prvWinPcapRecvThread ( void *pvParam )\r
-{\r
-       ( void ) pvParam;\r
-\r
-       /* THIS IS A WINDOWS THREAD - DO NOT ATTEMPT ANY FREERTOS CALLS OR TO PRINT\r
-       OUT MESSAGES HERE. */\r
-\r
-       for( ;; )\r
-       {\r
-               pcap_dispatch( pxOpenedInterfaceHandle, 1, pcap_callback, ( u_char * ) "mydata" );\r
-       }\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-DWORD WINAPI prvWinPcapSendThread( void *pvParam )\r
-{\r
-size_t xLength;\r
-uint8_t ucBuffer[ ipconfigNETWORK_MTU + ipSIZE_OF_ETH_HEADER ];\r
-static char cErrorMessage[ 1024 ];\r
-const DWORD xMaxMSToWait = 1000;\r
-\r
-       /* THIS IS A WINDOWS THREAD - DO NOT ATTEMPT ANY FREERTOS CALLS OR TO PRINT\r
-       OUT MESSAGES HERE. */\r
-\r
-       /* Remove compiler warnings about unused parameters. */\r
-       ( void ) pvParam;\r
-\r
-       for( ;; )\r
-       {\r
-               /* Wait until notified of something to send. */\r
-               WaitForSingleObject( pvSendEvent, xMaxMSToWait );\r
-\r
-               /* Is there more than the length value stored in the circular buffer\r
-               used to pass data from the FreeRTOS simulator into this Win32 thread? */\r
-               while( uxStreamBufferGetSize( xSendBuffer ) > sizeof( xLength ) )\r
-               {\r
-                       uxStreamBufferGet( xSendBuffer, 0, ( uint8_t * ) &xLength, sizeof( xLength ), pdFALSE );\r
-                       uxStreamBufferGet( xSendBuffer, 0, ( uint8_t* ) ucBuffer, xLength, pdFALSE );\r
-                       if( pcap_sendpacket( pxOpenedInterfaceHandle, ucBuffer, xLength  ) != 0 )\r
-                       {\r
-                               ulWinPCAPSendFailures++;\r
-                       }\r
-               }\r
-       }\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-static void prvInterruptSimulatorTask( void *pvParameters )\r
-{\r
-struct pcap_pkthdr xHeader;\r
-static struct pcap_pkthdr *pxHeader;\r
-const uint8_t *pucPacketData;\r
-uint8_t ucRecvBuffer[ ipconfigNETWORK_MTU + ipSIZE_OF_ETH_HEADER ];\r
-NetworkBufferDescriptor_t *pxNetworkBuffer;\r
-IPStackEvent_t xRxEvent = { eNetworkRxEvent, NULL };\r
-eFrameProcessingResult_t eResult;\r
-\r
-       /* Remove compiler warnings about unused parameters. */\r
-       ( void ) pvParameters;\r
-\r
-       for( ;; )\r
-       {\r
-               /* Does the circular buffer used to pass data from the Win32 thread that\r
-               handles WinPCAP Rx into the FreeRTOS simulator contain another packet? */\r
-               if( uxStreamBufferGetSize( xRecvBuffer ) > sizeof( xHeader ) )\r
-               {\r
-                       /* Get the next packet. */\r
-                       uxStreamBufferGet( xRecvBuffer, 0, (uint8_t*)&xHeader, sizeof( xHeader ), pdFALSE );\r
-                       uxStreamBufferGet( xRecvBuffer, 0, (uint8_t*)ucRecvBuffer, ( size_t ) xHeader.len, pdFALSE );\r
-                       pucPacketData = ucRecvBuffer;\r
-                       pxHeader = &xHeader;\r
-\r
-                       iptraceNETWORK_INTERFACE_RECEIVE();\r
-\r
-                       /* Check for minimal size. */\r
-                       if( pxHeader->len >= sizeof( EthernetHeader_t ) )\r
-                       {\r
-                               eResult = ipCONSIDER_FRAME_FOR_PROCESSING( pucPacketData );\r
-                       }\r
-                       else\r
-                       {\r
-                               eResult = eReleaseBuffer;\r
-                       }\r
-\r
-                       if( eResult == eProcessBuffer )\r
-                       {\r
-                               /* Will the data fit into the frame buffer? */\r
-                               if( pxHeader->len <= ipTOTAL_ETHERNET_FRAME_SIZE )\r
-                               {\r
-                                       /* Obtain a buffer into which the data can be placed.  This\r
-                                       is only an interrupt simulator, not a real interrupt, so it\r
-                                       is ok to call the task level function here, but note that\r
-                                       some buffer implementations cannot be called from a real\r
-                                       interrupt. */\r
-                                       pxNetworkBuffer = pxGetNetworkBufferWithDescriptor( pxHeader->len, 0 );\r
-\r
-                                       if( pxNetworkBuffer != NULL )\r
-                                       {\r
-                                               memcpy( pxNetworkBuffer->pucEthernetBuffer, pucPacketData, pxHeader->len );\r
-                                               pxNetworkBuffer->xDataLength = ( size_t ) pxHeader->len;\r
-\r
-                                               #if( niDISRUPT_PACKETS == 1 )\r
-                                               {\r
-                                                       pxNetworkBuffer = vRxFaultInjection( pxNetworkBuffer, pucPacketData );\r
-                                               }\r
-                                               #endif /* niDISRUPT_PACKETS */\r
-\r
-                                               if( pxNetworkBuffer != NULL )\r
-                                               {\r
-                                                       xRxEvent.pvData = ( void * ) pxNetworkBuffer;\r
-\r
-                                                       /* Data was received and stored.  Send a message to\r
-                                                       the IP task to let it know. */\r
-                                                       if( xSendEventStructToIPTask( &xRxEvent, ( TickType_t ) 0 ) == pdFAIL )\r
-                                                       {\r
-                                                               /* The buffer could not be sent to the stack so\r
-                                                               must be released again.  This is only an\r
-                                                               interrupt simulator, not a real interrupt, so it\r
-                                                               is ok to use the task level function here, but\r
-                                                               note no all buffer implementations will allow\r
-                                                               this function to be executed from a real\r
-                                                               interrupt. */\r
-                                                               vReleaseNetworkBufferAndDescriptor( pxNetworkBuffer );\r
-                                                               iptraceETHERNET_RX_EVENT_LOST();\r
-                                                       }\r
-                                               }\r
-                                               else\r
-                                               {\r
-                                                       /* The packet was already released or stored inside\r
-                                                       vRxFaultInjection().  Don't release it here. */\r
-                                               }\r
-                                       }\r
-                                       else\r
-                                       {\r
-                                               iptraceETHERNET_RX_EVENT_LOST();\r
-                                       }\r
-                               }\r
-                               else\r
-                               {\r
-                                       /* Log that a packet was dropped because it would have\r
-                                       overflowed the buffer, but there may be more buffers to\r
-                                       process. */\r
-                               }\r
-                       }\r
-               }\r
-               else\r
-               {\r
-                       /* There is no real way of simulating an interrupt.  Make sure\r
-                       other tasks can run. */\r
-                       vTaskDelay( configWINDOWS_MAC_INTERRUPT_SIMULATOR_DELAY );\r
-               }\r
-       }\r
-}\r
-/*-----------------------------------------------------------*/\r
-\r
-static const char *prvRemoveSpaces( char *pcBuffer, int aBuflen, const char *pcMessage )\r
-{\r
-       char *pcTarget = pcBuffer;\r
-\r
-       /* Utility function used to formap messages being printed only. */\r
-       while( ( *pcMessage != 0 ) && ( pcTarget < ( pcBuffer + aBuflen - 1 ) ) )\r
-       {\r
-               *( pcTarget++ ) = *pcMessage;\r
-\r
-               if( isspace( *pcMessage ) != pdFALSE )\r
-               {\r
-                       while( isspace( *pcMessage ) != pdFALSE )\r
-                       {\r
-                               pcMessage++;\r
-                       }\r
-               }\r
-               else\r
-               {\r
-                       pcMessage++;\r
-               }\r
-       }\r
-\r
-       *pcTarget = '\0';\r
-\r
-       return pcBuffer;\r
-}\r
+/*
+FreeRTOS+TCP V2.0.11
+Copyright (C) 2017 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+ http://aws.amazon.com/freertos
+ http://www.FreeRTOS.org
+*/
+
+/* WinPCap includes. */
+#define HAVE_REMOTE
+#include "pcap.h"
+
+/* FreeRTOS includes. */
+#include "FreeRTOS.h"
+#include "task.h"
+#include "semphr.h"
+
+/* FreeRTOS+TCP includes. */
+#include "FreeRTOS_IP.h"
+#include "FreeRTOS_IP_Private.h"
+#include "NetworkBufferManagement.h"
+
+/* Thread-safe circular buffers are being used to pass data to and from the PCAP
+access functions. */
+#include "Win32-Extensions.h"
+#include "FreeRTOS_Stream_Buffer.h"
+
+/* Sizes of the thread safe circular buffers used to pass data to and from the
+WinPCAP Windows threads. */
+#define xSEND_BUFFER_SIZE  32768
+#define xRECV_BUFFER_SIZE  32768
+
+/* If ipconfigETHERNET_DRIVER_FILTERS_FRAME_TYPES is set to 1, then the Ethernet
+driver will filter incoming packets and only pass the stack those packets it
+considers need processing. */
+#if( ipconfigETHERNET_DRIVER_FILTERS_FRAME_TYPES == 0 )
+       #define ipCONSIDER_FRAME_FOR_PROCESSING( pucEthernetBuffer ) eProcessBuffer
+#else
+       #define ipCONSIDER_FRAME_FOR_PROCESSING( pucEthernetBuffer ) eConsiderFrameForProcessing( ( pucEthernetBuffer ) )
+#endif
+
+/* Used to insert test code only. */
+#define niDISRUPT_PACKETS      0
+
+/*-----------------------------------------------------------*/
+
+/*
+ * Windows threads that are outside of the control of the FreeRTOS simulator are
+ * used to interface with the WinPCAP libraries.
+ */
+DWORD WINAPI prvWinPcapRecvThread( void *pvParam );
+DWORD WINAPI prvWinPcapSendThread( void *pvParam );
+
+/*
+ * Print out a numbered list of network interfaces that are available on the
+ * host computer.
+ */
+static pcap_if_t * prvPrintAvailableNetworkInterfaces( void );
+
+/*
+ * Open the network interface.  The number of the interface to be opened is set
+ * by the configNETWORK_INTERFACE_TO_USE constant in FreeRTOSConfig.h.
+ */
+static void prvOpenSelectedNetworkInterface( pcap_if_t *pxAllNetworkInterfaces );
+static int prvOpenInterface( const char *pucName );
+
+/*
+ * Configure the capture filter to allow blocking reads, and to filter out
+ * packets that are not of interest to this demo.
+ */
+static void prvConfigureCaptureBehaviour( void );
+
+/*
+ * A function that simulates Ethernet interrupts by periodically polling the
+ * WinPCap interface for new data.
+ */
+static void prvInterruptSimulatorTask( void *pvParameters );
+
+/*
+ * Create the buffers that are used to pass data between the FreeRTOS simulator
+ * and the Win32 threads that manage WinPCAP.
+ */
+static void prvCreateThreadSafeBuffers( void );
+
+/*
+ * Utility function used to format print messages only.
+ */
+static const char *prvRemoveSpaces( char *pcBuffer, int aBuflen, const char *pcMessage );
+
+/*-----------------------------------------------------------*/
+
+/* Required by the WinPCap library. */
+static char cErrorBuffer[ PCAP_ERRBUF_SIZE ];
+
+/* An event used to wake up the Win32 thread that sends data through the WinPCAP
+library. */
+static void *pvSendEvent = NULL;
+
+/* _HT_ made the PCAP interface number configurable through the program's
+parameters in order to test in different machines. */
+static BaseType_t xConfigNetworkInterfaceToUse = configNETWORK_INTERFACE_TO_USE;
+
+/* Handles to the Windows threads that handle the PCAP IO. */
+static HANDLE vWinPcapRecvThreadHandle = NULL;
+static HANDLE vWinPcapSendThreadHandle = NULL;;
+
+/* The interface being used by WinPCap. */
+static pcap_t *pxOpenedInterfaceHandle = NULL;
+
+/* Circular buffers used by the PCAP Win32 threads. */
+static StreamBuffer_t *xSendBuffer = NULL;
+static StreamBuffer_t *xRecvBuffer = NULL;
+
+/* The MAC address initially set to the constants defined in FreeRTOSConfig.h. */
+extern uint8_t ucMACAddress[ 6 ];
+
+/* Logs the number of WinPCAP send failures, for viewing in the debugger only. */
+static volatile uint32_t ulWinPCAPSendFailures = 0;
+
+/*-----------------------------------------------------------*/
+
+BaseType_t xNetworkInterfaceInitialise( void )
+{
+BaseType_t xReturn = pdFALSE;
+pcap_if_t *pxAllNetworkInterfaces;
+
+       /* Query the computer the simulation is being executed on to find the
+       network interfaces it has installed. */
+       pxAllNetworkInterfaces = prvPrintAvailableNetworkInterfaces();
+
+       /* Open the network interface.  The number of the interface to be opened is
+       set by the configNETWORK_INTERFACE_TO_USE constant in FreeRTOSConfig.h.
+       Calling this function will set the pxOpenedInterfaceHandle variable.  If,
+       after calling this function, pxOpenedInterfaceHandle is equal to NULL, then
+       the interface could not be opened. */
+       if( pxAllNetworkInterfaces != NULL )
+       {
+               prvOpenSelectedNetworkInterface( pxAllNetworkInterfaces );
+       }
+
+       if( pxOpenedInterfaceHandle != NULL )
+       {
+               xReturn = pdPASS;
+       }
+
+       return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+static void prvCreateThreadSafeBuffers( void )
+{
+       /* The buffer used to pass data to be transmitted from a FreeRTOS task to
+       the Win32 thread that sends via the WinPCAP library. */
+       if( xSendBuffer == NULL)
+       {
+               xSendBuffer = ( StreamBuffer_t * ) malloc( sizeof( *xSendBuffer ) - sizeof( xSendBuffer->ucArray ) + xSEND_BUFFER_SIZE + 1 );
+               configASSERT( xSendBuffer );
+               memset( xSendBuffer, '\0', sizeof( *xSendBuffer ) - sizeof( xSendBuffer->ucArray ) );
+               xSendBuffer->LENGTH = xSEND_BUFFER_SIZE + 1;
+       }
+
+       /* The buffer used to pass received data from the Win32 thread that receives
+       via the WinPCAP library to the FreeRTOS task. */
+       if( xRecvBuffer == NULL)
+       {
+               xRecvBuffer = ( StreamBuffer_t * ) malloc( sizeof( *xRecvBuffer ) - sizeof( xRecvBuffer->ucArray ) + xRECV_BUFFER_SIZE + 1 );
+               configASSERT( xRecvBuffer );
+               memset( xRecvBuffer, '\0', sizeof( *xRecvBuffer ) - sizeof( xRecvBuffer->ucArray ) );
+               xRecvBuffer->LENGTH = xRECV_BUFFER_SIZE + 1;
+       }
+}
+/*-----------------------------------------------------------*/
+
+BaseType_t xNetworkInterfaceOutput( NetworkBufferDescriptor_t * const pxNetworkBuffer, BaseType_t bReleaseAfterSend )
+{
+size_t xSpace;
+
+       iptraceNETWORK_INTERFACE_TRANSMIT();
+       configASSERT( xIsCallingFromIPTask() == pdTRUE );
+
+       /* Both the length of the data being sent and the actual data being sent
+       are placed in the thread safe buffer used to pass data between the FreeRTOS
+       tasks and the Win32 thread that sends data via the WinPCAP library.  Drop
+       the packet if there is insufficient space in the buffer to hold both. */
+       xSpace = uxStreamBufferGetSpace( xSendBuffer );
+
+       if( ( pxNetworkBuffer->xDataLength <= ( ipconfigNETWORK_MTU + ipSIZE_OF_ETH_HEADER ) ) &&
+               ( xSpace >= ( pxNetworkBuffer->xDataLength + sizeof( pxNetworkBuffer->xDataLength ) ) ) )
+       {
+               /* First write in the length of the data, then write in the data
+               itself. */
+               uxStreamBufferAdd( xSendBuffer, 0, ( const uint8_t * ) &( pxNetworkBuffer->xDataLength ), sizeof( pxNetworkBuffer->xDataLength ) );
+               uxStreamBufferAdd( xSendBuffer, 0, ( const uint8_t * ) pxNetworkBuffer->pucEthernetBuffer, pxNetworkBuffer->xDataLength );
+       }
+       else
+       {
+               FreeRTOS_debug_printf( ( "xNetworkInterfaceOutput: send buffers full to store %lu\n", pxNetworkBuffer->xDataLength ) );
+       }
+
+       /* Kick the Tx task in either case in case it doesn't know the buffer is
+       full. */
+       SetEvent( pvSendEvent );
+
+       /* The buffer has been sent so can be released. */
+       if( bReleaseAfterSend != pdFALSE )
+       {
+               vReleaseNetworkBufferAndDescriptor( pxNetworkBuffer );
+       }
+
+       return pdPASS;
+}
+/*-----------------------------------------------------------*/
+
+static pcap_if_t * prvPrintAvailableNetworkInterfaces( void )
+{
+pcap_if_t * pxAllNetworkInterfaces = NULL, *xInterface;
+int32_t lInterfaceNumber = 1;
+char cBuffer[ 512 ];
+static BaseType_t xInvalidInterfaceDetected = pdFALSE;
+
+       if( xInvalidInterfaceDetected == pdFALSE )
+       {
+               if( pcap_findalldevs_ex( PCAP_SRC_IF_STRING, NULL, &pxAllNetworkInterfaces, cErrorBuffer ) == -1 )
+               {
+                       printf( "Could not obtain a list of network interfaces\n%s\n", cErrorBuffer );
+                       pxAllNetworkInterfaces = NULL;
+               }
+               else
+               {
+                       printf( "\r\n\r\nThe following network interfaces are available:\r\n\r\n" );
+               }
+
+               if( pxAllNetworkInterfaces != NULL )
+               {
+                       /* Print out the list of network interfaces.  The first in the list
+                       is interface '1', not interface '0'. */
+                       for( xInterface = pxAllNetworkInterfaces; xInterface != NULL; xInterface = xInterface->next )
+                       {
+                               /* The descriptions of the devices can be full of spaces, clean them
+                               a little.  printf() can only be used here because the network is not
+                               up yet - so no other network tasks will be running. */
+                               printf( "Interface %d - %s\n", lInterfaceNumber, prvRemoveSpaces( cBuffer, sizeof( cBuffer ), xInterface->name ) );
+                               printf( "              (%s)\n", prvRemoveSpaces(cBuffer, sizeof( cBuffer ), xInterface->description ? xInterface->description : "No description" ) );
+                               printf( "\n" );
+                               lInterfaceNumber++;
+                       }
+               }
+
+               if( lInterfaceNumber == 1 )
+               {
+                       /* The interface number was never incremented, so the above for() loop
+                       did not execute meaning no interfaces were found. */
+                       printf( " \nNo network interfaces were found.\n" );
+                       pxAllNetworkInterfaces = NULL;
+               }
+
+               printf( "\r\nThe interface that will be opened is set by " );
+               printf( "\"configNETWORK_INTERFACE_TO_USE\", which\r\nshould be defined in FreeRTOSConfig.h\r\n" );
+
+               if( ( xConfigNetworkInterfaceToUse < 1L ) || ( xConfigNetworkInterfaceToUse >= lInterfaceNumber ) )
+               {
+                       printf( "\r\nERROR:  configNETWORK_INTERFACE_TO_USE is set to %d, which is an invalid value.\r\n", xConfigNetworkInterfaceToUse );
+                       printf( "Please set configNETWORK_INTERFACE_TO_USE to one of the interface numbers listed above,\r\n" );
+                       printf( "then re-compile and re-start the application.  Only Ethernet (as opposed to WiFi)\r\n" );
+                       printf( "interfaces are supported.\r\n\r\nHALTING\r\n\r\n\r\n" );
+                       xInvalidInterfaceDetected = pdTRUE;
+
+                       if( pxAllNetworkInterfaces != NULL )
+                       {
+                               /* Free the device list, as no devices are going to be opened. */
+                               pcap_freealldevs( pxAllNetworkInterfaces );
+                               pxAllNetworkInterfaces = NULL;
+                       }
+               }
+               else
+               {
+                       printf( "Attempting to open interface number %d.\n", xConfigNetworkInterfaceToUse );
+               }
+       }
+
+       return pxAllNetworkInterfaces;
+}
+/*-----------------------------------------------------------*/
+
+static int prvOpenInterface( const char *pucName )
+{
+static char pucInterfaceName[ 256 ];
+
+       if( pucName != NULL )
+       {
+               strncpy( pucInterfaceName, pucName, sizeof( pucInterfaceName ) );
+       }
+
+       pxOpenedInterfaceHandle = pcap_open(    pucInterfaceName,               /* The name of the selected interface. */
+                                                                                       ipTOTAL_ETHERNET_FRAME_SIZE, /* The size of the packet to capture. */
+                                                                                       PCAP_OPENFLAG_PROMISCUOUS,      /* Open in promiscuous mode as the MAC and
+                                                                                                                                               IP address is going to be "simulated", and
+                                                                                                                                               not be the real MAC and IP address.  This allows
+                                                                                                                                               traffic to the simulated IP address to be routed
+                                                                                                                                               to uIP, and traffic to the real IP address to be
+                                                                                                                                               routed to the Windows TCP/IP stack. */
+                                                                                       100,
+                                                                                       NULL,                                   /* No authentication is required as this is
+                                                                                                                                               not a remote capture session. */
+                                                                                       cErrorBuffer
+                                                                          );
+
+       if ( pxOpenedInterfaceHandle == NULL )
+       {
+               printf( "\n%s is not supported by WinPcap and cannot be opened\n", pucInterfaceName );
+               return 1;
+       }
+       else
+       {
+               /* Configure the capture filter to allow blocking reads, and to filter
+               out packets that are not of interest to this demo. */
+               prvConfigureCaptureBehaviour();
+       }
+       return 0;
+}
+/*-----------------------------------------------------------*/
+
+static void prvOpenSelectedNetworkInterface( pcap_if_t *pxAllNetworkInterfaces )
+{
+pcap_if_t *pxInterface;
+int32_t x;
+
+       /* Walk the list of devices until the selected device is located. */
+       pxInterface = pxAllNetworkInterfaces;
+       for( x = 0L; x < ( xConfigNetworkInterfaceToUse - 1L ); x++ )
+       {
+               pxInterface = pxInterface->next;
+       }
+
+       /* Open the selected interface. */
+       if( prvOpenInterface( pxInterface->name ) == 0 )
+       {
+               printf( "Successfully opened interface number %d.\n", x + 1 );
+       }
+       else
+       {
+               printf( "Failed to open interface number %d.\n", x + 1 );
+       }
+
+       /* The device list is no longer required. */
+       pcap_freealldevs( pxAllNetworkInterfaces );
+}
+/*-----------------------------------------------------------*/
+
+static void prvConfigureCaptureBehaviour( void )
+{
+struct bpf_program xFilterCode;
+uint32_t ulNetMask;
+
+       /* Set up a filter so only the packets of interest are passed to the IP
+       stack.  cErrorBuffer is used for convenience to create the string.  Don't
+       confuse this with an error message. */
+       sprintf( cErrorBuffer, "broadcast or multicast or ether host %x:%x:%x:%x:%x:%x",
+               ucMACAddress[0], ucMACAddress[1], ucMACAddress[2], ucMACAddress[3], ucMACAddress[4], ucMACAddress[5] );
+
+       ulNetMask = ( configNET_MASK3 << 24UL ) | ( configNET_MASK2 << 16UL ) | ( configNET_MASK1 << 8L ) | configNET_MASK0;
+
+       if( pcap_compile( pxOpenedInterfaceHandle, &xFilterCode, cErrorBuffer, 1, ulNetMask ) < 0 )
+       {
+               printf( "\nThe packet filter string is invalid\n" );
+       }
+       else
+       {
+               if( pcap_setfilter( pxOpenedInterfaceHandle, &xFilterCode ) < 0 )
+               {
+                       printf( "\nAn error occurred setting the packet filter.\n" );
+               }
+               /* When pcap_compile() succeeds, it allocates memory for the memory pointed to by the bpf_program struct 
+               parameter.pcap_freecode() will free that memory. */
+               pcap_freecode( &xFilterCode );
+       }
+
+       /* Create the buffers used to pass packets between the FreeRTOS simulator
+       and the Win32 threads that are handling WinPCAP. */
+       prvCreateThreadSafeBuffers();
+
+       if( pvSendEvent == NULL )
+       {
+               /* Create event used to signal the Win32 WinPCAP Tx thread. */
+               pvSendEvent = CreateEvent( NULL, FALSE, TRUE, NULL );
+
+               /* Create the Win32 thread that handles WinPCAP Rx. */
+               vWinPcapRecvThreadHandle = CreateThread(
+                       NULL,   /* Pointer to thread security attributes. */
+                       0,              /* Initial thread stack size, in bytes. */
+                       prvWinPcapRecvThread,   /* Pointer to thread function. */
+                       NULL,   /* Argument for new thread. */
+                       0,              /* Creation flags. */
+                       NULL );
+
+               /* Use the cores that are not used by the FreeRTOS tasks. */
+               SetThreadAffinityMask( vWinPcapRecvThreadHandle, ~0x01u );
+
+               /* Create the Win32 thread that handlers WinPCAP Tx. */
+               vWinPcapSendThreadHandle = CreateThread(
+                       NULL,   /* Pointer to thread security attributes. */
+                       0,              /* initial thread stack size, in bytes. */
+                       prvWinPcapSendThread,   /* Pointer to thread function. */
+                       NULL,   /* Argument for new thread. */
+                       0,              /* Creation flags. */
+                       NULL );
+
+               /* Use the cores that are not used by the FreeRTOS tasks. */
+               SetThreadAffinityMask( vWinPcapSendThreadHandle, ~0x01u );
+
+               /* Create a task that simulates an interrupt in a real system.  This will
+               block waiting for packets, then send a message to the IP task when data
+               is available. */
+               xTaskCreate( prvInterruptSimulatorTask, "MAC_ISR", configMINIMAL_STACK_SIZE, NULL, configMAC_ISR_SIMULATOR_PRIORITY, NULL );
+       }
+}
+/*-----------------------------------------------------------*/
+
+/* WinPCAP function. */
+void pcap_callback( u_char *user, const struct pcap_pkthdr *pkt_header, const u_char *pkt_data )
+{
+       (void)user;
+
+       /* THIS IS CALLED FROM A WINDOWS THREAD - DO NOT ATTEMPT ANY FREERTOS CALLS
+       OR TO PRINT OUT MESSAGES HERE. */
+
+       /* Pass data to the FreeRTOS simulator on a thread safe circular buffer. */
+       if( ( pkt_header->caplen <= ( ipconfigNETWORK_MTU + ipSIZE_OF_ETH_HEADER ) ) &&
+               ( uxStreamBufferGetSpace( xRecvBuffer ) >= ( ( ( size_t ) pkt_header->caplen ) + sizeof( *pkt_header ) ) ) )
+       {
+               uxStreamBufferAdd( xRecvBuffer, 0, ( const uint8_t* ) pkt_header, sizeof( *pkt_header ) );
+               uxStreamBufferAdd( xRecvBuffer, 0, ( const uint8_t* ) pkt_data, ( size_t ) pkt_header->caplen );
+       }
+}
+/*-----------------------------------------------------------*/
+
+DWORD WINAPI prvWinPcapRecvThread ( void *pvParam )
+{
+       ( void ) pvParam;
+
+       /* THIS IS A WINDOWS THREAD - DO NOT ATTEMPT ANY FREERTOS CALLS OR TO PRINT
+       OUT MESSAGES HERE. */
+
+       for( ;; )
+       {
+               pcap_dispatch( pxOpenedInterfaceHandle, 1, pcap_callback, ( u_char * ) "mydata" );
+       }
+}
+/*-----------------------------------------------------------*/
+
+DWORD WINAPI prvWinPcapSendThread( void *pvParam )
+{
+size_t xLength;
+uint8_t ucBuffer[ ipconfigNETWORK_MTU + ipSIZE_OF_ETH_HEADER ];
+static char cErrorMessage[ 1024 ];
+const DWORD xMaxMSToWait = 1000;
+
+       /* THIS IS A WINDOWS THREAD - DO NOT ATTEMPT ANY FREERTOS CALLS OR TO PRINT
+       OUT MESSAGES HERE. */
+
+       /* Remove compiler warnings about unused parameters. */
+       ( void ) pvParam;
+
+       for( ;; )
+       {
+               /* Wait until notified of something to send. */
+               WaitForSingleObject( pvSendEvent, xMaxMSToWait );
+
+               /* Is there more than the length value stored in the circular buffer
+               used to pass data from the FreeRTOS simulator into this Win32 thread? */
+               while( uxStreamBufferGetSize( xSendBuffer ) > sizeof( xLength ) )
+               {
+                       uxStreamBufferGet( xSendBuffer, 0, ( uint8_t * ) &xLength, sizeof( xLength ), pdFALSE );
+                       uxStreamBufferGet( xSendBuffer, 0, ( uint8_t* ) ucBuffer, xLength, pdFALSE );
+                       if( pcap_sendpacket( pxOpenedInterfaceHandle, ucBuffer, xLength  ) != 0 )
+                       {
+                               ulWinPCAPSendFailures++;
+                       }
+               }
+       }
+}
+/*-----------------------------------------------------------*/
+
+static void prvInterruptSimulatorTask( void *pvParameters )
+{
+struct pcap_pkthdr xHeader;
+static struct pcap_pkthdr *pxHeader;
+const uint8_t *pucPacketData;
+uint8_t ucRecvBuffer[ ipconfigNETWORK_MTU + ipSIZE_OF_ETH_HEADER ];
+NetworkBufferDescriptor_t *pxNetworkBuffer;
+IPStackEvent_t xRxEvent = { eNetworkRxEvent, NULL };
+eFrameProcessingResult_t eResult;
+
+       /* Remove compiler warnings about unused parameters. */
+       ( void ) pvParameters;
+
+       for( ;; )
+       {
+               /* Does the circular buffer used to pass data from the Win32 thread that
+               handles WinPCAP Rx into the FreeRTOS simulator contain another packet? */
+               if( uxStreamBufferGetSize( xRecvBuffer ) > sizeof( xHeader ) )
+               {
+                       /* Get the next packet. */
+                       uxStreamBufferGet( xRecvBuffer, 0, (uint8_t*)&xHeader, sizeof( xHeader ), pdFALSE );
+                       uxStreamBufferGet( xRecvBuffer, 0, (uint8_t*)ucRecvBuffer, ( size_t ) xHeader.len, pdFALSE );
+                       pucPacketData = ucRecvBuffer;
+                       pxHeader = &xHeader;
+
+                       iptraceNETWORK_INTERFACE_RECEIVE();
+
+                       /* Check for minimal size. */
+                       if( pxHeader->len >= sizeof( EthernetHeader_t ) )
+                       {
+                               eResult = ipCONSIDER_FRAME_FOR_PROCESSING( pucPacketData );
+                       }
+                       else
+                       {
+                               eResult = eReleaseBuffer;
+                       }
+
+                       if( eResult == eProcessBuffer )
+                       {
+                               /* Will the data fit into the frame buffer? */
+                               if( pxHeader->len <= ipTOTAL_ETHERNET_FRAME_SIZE )
+                               {
+                                       /* Obtain a buffer into which the data can be placed.  This
+                                       is only an interrupt simulator, not a real interrupt, so it
+                                       is ok to call the task level function here, but note that
+                                       some buffer implementations cannot be called from a real
+                                       interrupt. */
+                                       pxNetworkBuffer = pxGetNetworkBufferWithDescriptor( pxHeader->len, 0 );
+
+                                       if( pxNetworkBuffer != NULL )
+                                       {
+                                               memcpy( pxNetworkBuffer->pucEthernetBuffer, pucPacketData, pxHeader->len );
+                                               pxNetworkBuffer->xDataLength = ( size_t ) pxHeader->len;
+
+                                               #if( niDISRUPT_PACKETS == 1 )
+                                               {
+                                                       pxNetworkBuffer = vRxFaultInjection( pxNetworkBuffer, pucPacketData );
+                                               }
+                                               #endif /* niDISRUPT_PACKETS */
+
+                                               if( pxNetworkBuffer != NULL )
+                                               {
+                                                       xRxEvent.pvData = ( void * ) pxNetworkBuffer;
+
+                                                       /* Data was received and stored.  Send a message to
+                                                       the IP task to let it know. */
+                                                       if( xSendEventStructToIPTask( &xRxEvent, ( TickType_t ) 0 ) == pdFAIL )
+                                                       {
+                                                               /* The buffer could not be sent to the stack so
+                                                               must be released again.  This is only an
+                                                               interrupt simulator, not a real interrupt, so it
+                                                               is ok to use the task level function here, but
+                                                               note no all buffer implementations will allow
+                                                               this function to be executed from a real
+                                                               interrupt. */
+                                                               vReleaseNetworkBufferAndDescriptor( pxNetworkBuffer );
+                                                               iptraceETHERNET_RX_EVENT_LOST();
+                                                       }
+                                               }
+                                               else
+                                               {
+                                                       /* The packet was already released or stored inside
+                                                       vRxFaultInjection().  Don't release it here. */
+                                               }
+                                       }
+                                       else
+                                       {
+                                               iptraceETHERNET_RX_EVENT_LOST();
+                                       }
+                               }
+                               else
+                               {
+                                       /* Log that a packet was dropped because it would have
+                                       overflowed the buffer, but there may be more buffers to
+                                       process. */
+                               }
+                       }
+               }
+               else
+               {
+                       /* There is no real way of simulating an interrupt.  Make sure
+                       other tasks can run. */
+                       vTaskDelay( configWINDOWS_MAC_INTERRUPT_SIMULATOR_DELAY );
+               }
+       }
+}
+/*-----------------------------------------------------------*/
+
+static const char *prvRemoveSpaces( char *pcBuffer, int aBuflen, const char *pcMessage )
+{
+       char *pcTarget = pcBuffer;
+
+       /* Utility function used to formap messages being printed only. */
+       while( ( *pcMessage != 0 ) && ( pcTarget < ( pcBuffer + aBuflen - 1 ) ) )
+       {
+               *( pcTarget++ ) = *pcMessage;
+
+               if( isspace( *pcMessage ) != pdFALSE )
+               {
+                       while( isspace( *pcMessage ) != pdFALSE )
+                       {
+                               pcMessage++;
+                       }
+               }
+               else
+               {
+                       pcMessage++;
+               }
+       }
+
+       *pcTarget = '\0';
+
+       return pcBuffer;
+}